diff options
| author | Alvaro Herrera | 2017-04-01 19:10:04 +0000 |
|---|---|---|
| committer | Alvaro Herrera | 2017-04-01 19:10:04 +0000 |
| commit | c655899ba9ae2a0d24e99c797167c33e0cfa0820 (patch) | |
| tree | 5493791074d6624cf5ce44313a870846d4563f97 /src/include/access | |
| parent | 3a82129a40a3a2987356d4051e017fd456876c8d (diff) | |
BRIN de-summarization
When the BRIN summary tuple for a page range becomes too "wide" for the
values actually stored in the table (because the tuples that were
present originally are no longer present due to updates or deletes), it
can be useful to remove the outdated summary tuple, so that a future
summarization can install a tighter summary.
This commit introduces a SQL-callable interface to do so.
Author: Álvaro Herrera
Reviewed-by: Eiji Seki
Discussion: https://postgr.es/m/20170228045643.n2ri74ara4fhhfxf@alvherre.pgsql
Diffstat (limited to 'src/include/access')
| -rw-r--r-- | src/include/access/brin_revmap.h | 1 | ||||
| -rw-r--r-- | src/include/access/brin_xlog.h | 20 |
2 files changed, 20 insertions, 1 deletions
diff --git a/src/include/access/brin_revmap.h b/src/include/access/brin_revmap.h index 2ec4169f6d5..7fdcf877f4b 100644 --- a/src/include/access/brin_revmap.h +++ b/src/include/access/brin_revmap.h @@ -36,5 +36,6 @@ extern void brinSetHeapBlockItemptr(Buffer rmbuf, BlockNumber pagesPerRange, extern BrinTuple *brinGetTupleForHeapBlock(BrinRevmap *revmap, BlockNumber heapBlk, Buffer *buf, OffsetNumber *off, Size *size, int mode, Snapshot snapshot); +extern bool brinRevmapDesummarizeRange(Relation idxrel, BlockNumber heapBlk); #endif /* BRIN_REVMAP_H */ diff --git a/src/include/access/brin_xlog.h b/src/include/access/brin_xlog.h index 33ceb34ea53..89ed334a018 100644 --- a/src/include/access/brin_xlog.h +++ b/src/include/access/brin_xlog.h @@ -33,7 +33,7 @@ #define XLOG_BRIN_UPDATE 0x20 #define XLOG_BRIN_SAMEPAGE_UPDATE 0x30 #define XLOG_BRIN_REVMAP_EXTEND 0x40 -#define XLOG_BRIN_REVMAP_VACUUM 0x50 +#define XLOG_BRIN_DESUMMARIZE 0x50 #define XLOG_BRIN_OPMASK 0x70 /* @@ -124,6 +124,24 @@ typedef struct xl_brin_revmap_extend #define SizeOfBrinRevmapExtend (offsetof(xl_brin_revmap_extend, targetBlk) + \ sizeof(BlockNumber)) +/* + * This is what we need to know about a range de-summarization + * + * Backup block 0: revmap page + * Backup block 1: regular page + */ +typedef struct xl_brin_desummarize +{ + BlockNumber pagesPerRange; + /* page number location to set to invalid */ + OffsetNumber heapBlk; + /* offset of item to delete in regular index page */ + OffsetNumber regOffset; +} xl_brin_desummarize; + +#define SizeOfBrinDesummarize (offsetof(xl_brin_desummarize, regOffset) + \ + sizeof(OffsetNumber)) + extern void brin_redo(XLogReaderState *record); extern void brin_desc(StringInfo buf, XLogReaderState *record); |